1. Field of the Invention
The present invention is directed to the field of electrical connector contacts or terminals and connector assemblies and in particular of the type having contact forces caused by torsional loading of the contact terminals.
2. Description of the Prior Art
The contact forces between the components of a mating pair of electrical connectors is of paramount importance in forming a reliable connection. This contact force is usually derived from the elastic characteristics of either or both of the connector terminal members.
Many contact designs utilize the principle of bending one or more terminal fingers that are configured as cantilevered beams. The bending forces give rise to a contact force between the terminals. Relatively high flexure of the beam is required to assure sufficient force thereby resulting in high bending stresses. This construction, along with the clearance needed to accommodate the flexing of the contact, precludes close contact spacing in a multi-contact assembly having high density connectors or multiple connectors in a confined space. With the continuing trend toward miniaturization, it becomes difficult and expensive to manufacture flexing beam systems that give satisfactory performance.
Terminals have been designed that develop torsional loads for creating contact forces between connector terminals. Torsional loading by means of rotation of a terminal about its own longitudinal axis allows for a compact design. Some prior art devices that teach this type of construction include U.S. Pat. No. 4,941,853 to Harwath; U.S. Pat. No. 4,105,277 to Jacobs; U.S. Pat. No. 2,924,807 to Field; and U.S. Pat. No. 4,735,588 to Bird et al. None of these devices discloses a construction where the socket or female member of the contact pair deforms. It is rather the pin or male member that is forced into conformance with the socket and as a result insertion forces are frequently unacceptably high with a consequent low cycle life because of degradation of the contact surfaces.